package com.yupi.yupicturebackend.manager.upload;

import cn.hutool.core.io.FileUtil;
import cn.hutool.core.util.StrUtil;
import cn.hutool.http.HttpResponse;
import cn.hutool.http.HttpStatus;
import cn.hutool.http.HttpUtil;
import cn.hutool.http.Method;
import com.yupi.yupicturebackend.exception.BusinessException;
import com.yupi.yupicturebackend.exception.ErrorCode;
import com.yupi.yupicturebackend.exception.ThrowUtils;
import org.springframework.stereotype.Service;

import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Arrays;
import java.util.List;

/**
 * url 图片上传
 */
@Service
public class UrlPictureUpload extends PictureUploadTemplate {


    @Override
    protected void validPicture(Object intputSource) {
        String fileUrl = (String) intputSource;
        //1.校验非空
        ThrowUtils.throwIf(StrUtil.isBlank(fileUrl), ErrorCode.PARAMS_ERROR,"文件地址为空");
        //2.校验URL格式
        try {
            new URL(fileUrl);
        } catch (MalformedURLException e) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR,"文件格式不正确");
        }
        //3.校验URL协议
        ThrowUtils.throwIf(!fileUrl.startsWith("http://") && !fileUrl.startsWith("https://")
                ,ErrorCode.PARAMS_ERROR,"仅支持 http 或者 https 的文件协议");
        //4.发送HEAD请求验证文件是否存在

        HttpResponse httpResponse = null;
        try {
            httpResponse = HttpUtil.createRequest(Method.HEAD, fileUrl).execute();
            //未正常返回，无需执行其他操作
            if(httpResponse.getStatus() != HttpStatus.HTTP_OK){
                return;
            }
            //5.文件存在，校验文件类型
            String contentType = httpResponse.header("Content-Type");
            if(StrUtil.isNotBlank(contentType)){
                final List<String> ALLOW_CONTENT_TYPES = Arrays.asList("image/jpeg", "image/jpg", "image/png", "image/webp");
                ThrowUtils.throwIf(!ALLOW_CONTENT_TYPES.contains(contentType.toLowerCase()),
                        ErrorCode.PARAMS_ERROR, "文件类型错误");
            }
            //6.文件存在，校验文件大小
            String contentLengthStr = httpResponse.header("Content-length");
            if(StrUtil.isNotBlank(contentLengthStr)){

                try {
                    long contentLength = Long.parseLong(contentLengthStr);
                    final long ONE_MB = 1024 * 1024;
                    ThrowUtils.throwIf(contentLength>2*ONE_MB,ErrorCode.PARAMS_ERROR,"文件超过 2MB");
                }catch (NumberFormatException e){
                    throw new BusinessException(ErrorCode.PARAMS_ERROR,"文件大小格式异常");
                }
            }
        }finally {
            if(httpResponse != null){
                httpResponse.close();
            }
        }
    }


    @Override
    protected String getOriginalFilename(Object intputSource) {
        String fileUrl = (String) intputSource;
        return FileUtil.mainName(fileUrl);
    }

    @Override
    protected void processFile(Object intputSource, File file) throws Exception {
        String fileUrl = (String) intputSource;
        HttpUtil.downloadFile(fileUrl, file);

    }
}
